Music accompaniment systems have a long tradition in electronic organs used by one-man bands. Typically, the automated accompaniment produces a rhythm section, such as drums, bass, or a harmony instrument (e.g., a piano). The rhythm section can perform in a given tempo (e.g., 120 beat-per-minute), style (e.g., bossa nova) and set of chords (e.g., recorded live with the left hand of the organ player). The accompaniment system can then create a bass line and rhythmical harmonic chord structure from the played chord and progressing chord structure. Similar systems, like Band-in a Box™, create a play-along band from a manually-entered chord sheet using a software synthesizer for drums, bass, and harmony instruments. Other approaches focus on classical music.